product substitution
noun
ukus [ C ] COMMERCE
a product that can be used instead of a similar product:
If an item is out of stock, a product substitution is offered in its place.
[ U ]
a situation where a cheap product has been used instead of a more expensive one in order to reduce costs:
Investigators believe unauthorized product substitution may be to blame for the accident, in which poor quality parts had been used to repair the plane.